Hacer Calculadora Eb Visual Studio

Public Class Form1
Public numero1 As String
Public operador As String
Public numero2 As String
Public resultado As String

Private Sub pantalla_TextChanged(ByVal sender AsSystem.Object, ByVal e As System.EventArgs) Handles pantalla.TextChanged

End Sub

Private Sub Button6_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) HandlesButton6.Click
pantalla.Text = pantalla.Text & "5"
End Sub

Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
pantalla.Text =pantalla.Text & "9"
End Sub

Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click
pantalla.Text = pantalla.Text & "8"End Sub

Private Sub Button3_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button3.Click
pantalla.Text = pantalla.Text & "7"
End Sub

Private SubButton5_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button5.Click
pantalla.Text = pantalla.Text & "6"
End Sub

Private Sub Button7_Click(ByVal sender AsSystem.Object, ByVal e As System.EventArgs) Handles Button7.Click
pantalla.Text = pantalla.Text & "4"
End Sub

Private Sub Button9_Click(ByVal sender As System.Object, ByVal e AsSystem.EventArgs) Handles Button9.Click
pantalla.Text = pantalla.Text & "3"
End Sub

Private Sub Button10_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) HandlesButton10.Click
pantalla.Text = pantalla.Text & "2"
End Sub

Private Sub Button11_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button11.Clickpantalla.Text = pantalla.Text & "1"
End Sub

Private Sub Button13_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button13.Click
pantalla.Text =...